Question: What is the least common multiple of 20 and 4? Another way to say this is: $\lcm(20, 4) = {?}$
Explanation: The least common multiple is the smallest number that is a multiple of 20 and 4. We know that 20 x 4 (or 80) is a common multiple, but is it the least common multiple? Write out the multiples of 20 until we find a number divisible by 4. 20, So, 20 is the least common multiple of 20 and 4.